Really liking the overall tone/sound of this bass. I switched from GHS Precision flats (as in pic) to some used but boiled/cleaned D'Addario's (came on my '66 P so not certain what variety they are) and like the round-wound sound. I've had flats on this neck (attached to various bodies) since it was new, some 7 years now - so it's a fresh change. I just ordered my new favorites - D'Addario EXL170BT (nickel wound- balanced tension 45/60/80/107) I have the beefier EXL 160BT (50/67/90/120) on the '66 P and love them on that bass - matches well with the C neck and 'old-school' tone. Apparently James Jamerson liked the big 'cables' on his Motown-mojo P. I've used and liked the GHS Progressives for years but I just felt it was time for a change. It's no surprise that you see so many of the D'Addario multicolored ball-ends when people are showing off their basses here on tb.
Speaking of flats, I use GHS & Thomastik-Infeld on a couple basses, but my fave (on my '66 trib J) is LaBella Deep Talkin' Bass 750FS (45/65/85/105) - silky smooth and great tone.
Hey JIO
Enjoyed reading about your string adventures. Wow, such a personal thing I suppose and so nice to hear about what works for you.
Back in the early days I used Roto SwingBass rounds on my '72 Jazz and my Rick - and yes, I either boiled them or had new ones for each show. We got a deal with Dave Holcomb at GHS a little later and I used GHS exclusively. I mean for me - the magic in that bright piano-like sound was always amazing with those spanking new rounds. It's so funny when I think back on it - I can send you tapes of my playing "live" before we made our studio records and you won't even believe it was me! Totally Wetton/Lake/Squier "live" tonally but when we got into the studio Ken Scott really had a huge influence on me, right or wrong. We recorded a few tracks with the Rick and rounds through my Hiwatt (and some Marshalls and other amps at A&M) and he sat me down and we played with the drum and bass thing. In A-B tests he showed me the power of the rhythm section working as one with a more round full deep tone - and at least in the Happy the Man context, and I really bought into it. There was a power and a magic for me in the way a rounder warmer tone blended with the kick and caused the rhythm section to "breathe together" in a way I wasn't accustomed to. Again - in the HTM context.
Funny thing is - a few days later I got the PRS from Paul - it arrived UPS from Annapolis. I opened it up and we plugged it in. My greatest memory of that is Ken dialing through the 9 position rotary switch and being delighted. The drag for me is that Paul had abandoned the GHS strings I had given him before i left for L.A. in favor of D'Addario "Super Soft" Half Rounds - which the bass came strung with. I was pissed, frankly and I told Ken I was going to call Paul right away and find out what gives. Ken said - wait - before you call him let's record this track "Knee Bitten Nymphs In Limbo" - the only track which I wasn't that happy with using the Rick. I nailed it in one take and Ken just looked at me and said: "My God man, don't change a thing - this bass is one of the best I have ever heard anywhere - exactly as it is!"
So long story short (I know, I know, it is already REALLY long) I called Paul and he told me that for this bass D'Addario were my friends and I should never under any circumstances use anything else. I will spare you the details unless anyone really want to know - but I have been a D'Addario guy since 1978.
So fast forward - I have certain basses that have rounds, for recording only - end of story. DR sent me a big sample batch of strings a number of years ago, so when I need rounds I pull one of those sets out. If and when I finally run out I will get some from D'Addario. I just renewed my D'Addario deal and got a dozen or so sets friday - all Half Rounds with a couple of sets of Chromes.
I find that rounds do not give me the round full deep sound that half's give me with the tone rolled back. They tend to sound thinner and almost "nasally" to me. I can't live with that so my stage basses always have half rounds.
Like I said - strings are a highly personal thing - but it is always so interesting to compare notes....
Like I said at one point, it fully relieved my own gas for a real '66 which is out of reach monetarily. It's a bit heavy (10lbs) but otherwise sounds and plays great and the ideal bass style-wise for my Bond Girl band. Gotta look sharp playing the music of James Bond! 
